Illinois Counties

There are one hundred and two counties in Illinois. St. Clair County was the first county established in what is today Illinois. Most counties in Illinois were named after early American leaders, especially of the American Revolutionary War, as well as soldiers from the Battle of Tippecanoe and the War of 1812.

Illinois Counties: History and Information

Find a brief history of Illinois Counties

The State of Illinois is the 21st to be admitted to the
Union. Illinois is the most populous and demographically diverse Midwestern state and the fifth most populous in the
nation.

There are 102 counties in the state of Illinois. Most counties in Illinois were named after early American leaders, especially of the American Revolutionary War, as well as soldiers from the Battle of Tippecanoe and the War
of 1812. Some are named after natural features or counties in other states. Some are named for early Illinois leaders. Two counties are named for Native American tribes, and
one bears the name of a plant used as a food source by Native Americans.

While it does have a city, Illinois does not have a Lincoln County named after its favorite son, Abraham Lincoln; it does, however, have a Douglas County (founded 1859) named
after his political rival Stephen A. Douglas. It also has Calhoun County (founded 1825), named after John C. Calhoun, outspoken for his southern views in the years preceding
the American Civil War. Several of the counties are named after Southerners, reflecting the fact that Illinois was for a short time part of Virginia, and settled in its early
years by many Southerners. No counties are named after Northern heroes of the Civil War, mainly because the counties were all named before that war. The state does have a Lee
County named after the family of Robert E. Lee, who at one time served in Illinois. Illinois also has a singular distinction of having two counties named after the same person,
New York governor, DeWitt Clinton.